The new model looks at "dozens of factors pertaining to a couple’s fertility, age and health. . . [for example,] drugs given to boost fertility in the mother, the number of embryos with more than four cells reinserted, the woman’s age and weight, the age of the sperm provider and so on. . . . it can apply only to second attempts, since it relies on a history of the first IVF procedure to generate the data needed for the calculation. . . . [The factors include] the number of eggs retrieved [from the first IVF attempt], the number of embryos available for reinsertion [from the first IVF attempt[ and the woman’s previous history of live births."

It is hard to say how much the data will matter to couples. Utimately, the process simply makes what is already a crap shoot before, a somewhat more informed crap shoot where the odds are better known.